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<p>Hello,</p>
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</p>
<p>I recently installed GDAL with OpenCL and my tests have shown that running gdalwarp with '-wo "USE_OPENCL=FALSE"' gives better performance then running it without. I'm using Ubuntu 14.04 64-bit on an Intel i7-2720QM with an AMD Radeon HD 6400M series graphics
card. My OpenCL support is the AMD APP SDK and the AMD Catalyst driver, and I've confirmed that both the CPU and the GPU are seen as compute devices using clinfo. I've tried using both the CPU and the GPU as the OpenCL device and gotten the same results in
both cases. I've also tried on both a hard disk and an SSD with no luck. My test data is a large (3.4GB) GeoTIFF file, and the command is 'time gdalwarp -t_srs EPSG:3395 -r cubic gnc-world.tif gnc-world3395.tif'. Does anyone have any ideas why the performance
might be so bad?</p>
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</p>
<p>Thank you,</p>
<p>Greg<br>
</p>
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